MATERIAL UNIVERSE. 69 



ted to the humid surface. The vegetable growth, 

 although gigantic and rapid, was weak and suc- 

 culent, and the decay rapid. But organic life 

 was imparted to organic decay ; and the latter 

 became revivified, and subject to new organiza- 

 tion. 



Meantime, the shallow waters, together with 

 such places as had risen above them, were soon 

 covered with vegetable remains. And now com- 

 menced the formation of those immense beds of 

 carbon, or coal, which have since been discov- 

 ered, and which contribute so largely to the com- 

 fort, if not to the very existence, of man, in the 

 temperate and frigid zones. This coal forma- 

 tion, it is believed, could not have taken place 

 under the present low and variable temperature 

 of the earth's surface. This arrangement was 

 also necessary, at that time, to deprive the atmo- 

 sphere of the excess of carbonic acid, which 

 remained after the formation of carbonates and 

 vegetables, in order to render the air sufficiently 



